Medpot Minstrel: Hydroponics Medical Marijuana

Friday, May 25, 2007

How Close Should Your Light(s) Be?

Many growers of medicinal cannabis start their seedlings under fluorescent lights, since the illumination provided by this light source is gentle and perfectly adequate for germination and initial growth.

Then, when it comes time for transplanting the rooted seedlings into intermediary pots, some more intense lighting is required. So last week I moved my 15 pots into the periphery of my 600W High Pressure Sodium light, but I was sure to insert a blue-spectrum conversion bulb, since the growth stage of cannabis requires light on the blue end of the spectrum.

There are many theories as to providing lighting for growing cannabis. The mantra is often repeated—bring your light source as close as possible to the top of your plants. Use your hand as if you were testing the heat of a baby bottle. If the light burns your hand, move your light source up a notch.

I did all that and my plants still got burned! I was watering my seedlings with a half-strength nutrient mix composed of Sensi Grow Two-Part, my basic fert, B-52 an excellent B-complex vitamin, and the three root colonizers, Piranha, Tarantula, and Voodoo Juice.

I did this at four-hour intervals, so I only left my plants alone for a few hours. However, the old motor in my ventilation fan seized up and the heat of the light burned the tips of the top leaves of my young seedlings.

It is definitely not nute burn, since my nutrient mix is still at half strength. I was just about to increase it to full strength and start the week 1 regimen of growth feeding that I mentioned in last week’s posting, and then this happened.

It is a blow to your ego when you have taken every precaution possible, and then an old motor throws a wrench into the works. However, I took steps to save my investment. When you pay hundreds of dollars for premium seeds, you want to make sure that you get your money’s worth.

Instead of figuring out the distance between the young plants and the high intensity light mathematically, I went with the commonly held belief. Instead of testing the commonly held belief with my intellect, I went along with the crowd.

I know that a 600W High Pressure Sodium light generates 90,000 lumens a foot away from the source, 22,500 lumens two feet away, 9,999 lumens 3 feet away, and 6,428 lumens four feet away. Intensity equals light output divided by the distance squared.

So to figure out the lumens at five feet, I would have to divide 90,000 by five squared, or 25. So at five feet the light given off is 3600 lumens. At six feet it is 2500 lumens.

2500 lumens is the exact number that Jorge Cervantes suggests for seedlings in his “Indoor Mairjuana Horticulture.” So according to that, I should have had my seedlings six feet away from my light.

However, I placed my 15 pots around the periphery of the light, so I had them closer than that. Also, I didn’t use my head, I used the “hand test” so I brought my light source even closer to my young plants. With the fan going, it seemed cool enough under there.

The next time I’ll be sure to do the math. As is, I gave the young seedling another application of No Shock, which is an Advanced Nutrients product designed to minimize the shock of transplanting.

Also, since the extra heat dried out my grow medium between waterings and the young plants semi-wilted, I applied Revive. This is an Advanced Nutrients product engineered just for such occasions.

Revive contains super chelated micronutrients, such as iron and zinc, as well as macronutrients such as nitrogen and calcium, which are sucked up by the roots of the ailing plants and pretty soon they’re back to their vigorous former selves.

No Shock contains Golden Honey Fulvic Acid, derived from a richly organic mined substance called “leonardite,” as well as key nutrients, immune boosters, and root stimulators. If your plants have been stressed or shocked by transplanting or some other disastrous transition, No Shock will calm them down and set them back on the path of growth in no time.

Within 48 hours my 15 cannabis seedlings returned to normal with the HID light safely positioned 6 feet above the tops of the plants. Gradually, my light will be lowered to a distance of 3 feet above the plant canopy, in order to provide the 10,000 lumens of light called for by the experts for mature cannabis plants.

Ed Rosenthal took a reading at the 40th parallel and he measured 10,000 lumens in the sunlight on a clear day at noon. Why the 40th parallel, you ask? It is an imaginary line running 40 degrees above the Equator through such countries as Spain, Italy, Greece, Turkey, and comprising the border between Kansas and Nebraska in the United States.

Jorge Cervantes agrees with the 10,000 lumens prescription for adult marijuana plants. So I wonder if all those growers who claim that they bring their lights as close as possible to the tops of the plants are giving their plants too many lumens? Could some of those incidents of so-called nute burn be better explained by the proximity of high intensity lighting?

And if you nourish your plants properly with excellent plant nutrients such as the Sensi Two-Part and later Connoisseur A & B, your cannabis plants will grow thick and robust and you won’t have to be afraid of them stretching to reach the intense light.

posted by Wes @ 12:25 PM 0 comments links to this post

Friday, May 18, 2007

Curing Giant Buds, Planting Tiny Plants

How do you tell when your cannabis has finished drying? When your buds become brittle, crispy, and rollable into blunts. My plant tops with five or six large buds attached have reached this stage, so I carefully cut the wires holding them on the drying line and lowered the dried cannabis onto a clean surface for processing.

Using sterilized scissors, I cut the buds off the stems (I’ve manicured the buds while the plant was still fresh—manicuring them at this stage could result in trichome destruction and loss of potency) and carefully placed the buds into my 30 large, wide-mouth candy jars for curing.

I moved my finished, larger shelf into the walk-in drying closet and placed the 30 jars, now each containing a large bud, on the shelves. I put the lids on, but knowing full well that the lids will have to be removed once a day for a two-hour period to release any built up gases in the jars that could influence the curing process.

Some buds might require turning in order to fully dry. I keep the closet fan on medium setting while the jars are open in the dark, in order to keep the air circulating around the buds. I must confess seeing 30 humungous Connoisseur buds all lined up in candy jars is a beautiful sight!

Curing involves alternate periods of “sweating” your buds and continuing to dry them. If you notice any mold developing in the jars, then you’re doing too much sweating and too little drying. Make sure that there is good air circulation while the jar tops are open.

At the same time, the next generation of sinsemilla ladies is still in its infancy. Fifteen seedlings are still in the incubator, under a plastic humidity cover, growing under fluorescent lights. When it comes time to transplant these small plants, as soon as they have four tiny leaves, in addition to the two primary, cotyledon leaves, then they can be dipped into No Shock, to alleviate transplant stress.

The tiny seedlings in one-inch rockwool cubes have tiny root hairs that you have to be very careful with, when transplanting them. The seedlings, rockwool cube and all, are placed into the grow medium of your choice for further growth and development. In my case, it’s baked clay pebbles.

I don’t place them into the buckets of my six-bucket ebb and flow system immediately. For the time being I put baked clay pebbles into six-inch pots and cluster them under my 600W High Pressure Sodium light with a blue-light conversion bulb in its socket, rather than the red-spectrum regular HPS bulb.

I use my pre-mix tank to whip up my weekly nutrient solution, using Sensi Grow A & B as my primary fert, with the supplements and additives as called for by the Advanced Nutrients Nutrient Calculator, an invaluable tool.

For instance, in week 1 of the vegetative growth of the rooted seedlings, in my 72 Liter pre-mix tank I would pour 88.7 mL each of Sensi Grow A and Sensi Grow B, along with 115.2 mL of Mother Earth Blended Organic Super Tea Grow. The latter adds that much-needed organic touch for growers, like myself, using a synthetic base fertilizer.

Consisting of Canola, Crab, Fish, and Shrimp Meal, as well as Earthworm Castings, Alfalfa Extract, Citric Acid, and Sea Kelp, Mother Earth Super Tea has an NPK of 4.8-1.8-4.3, and is designed to enhance the fragrance, taste, and the quality of your buds.

Plant scientists have confirmed that sea kelp is full of potassium and micronutrients. In addition, cytokinins, auxins, and gibberlins can also be found in seaweed. These are natural plant growth hormones that are produced by plants as a matter of course.

Plants under stress, be it temperature, drought, or light related, are unable to produce these hormones. Therefore, supplying them through a supplement containing seaweed extract is a wise course of action. Cytokinins, auxins, and gibberlins are not only involved in plant growth, but also nutrient mobilization and distribution, germination, cell division, root development, flowering and seed formation. They regulate physiological plant processes.

I’ve discussed the importance of Humic and Fulvic acid before. During week 1 I pour 72 mL of each into the pre-mix tank, followed by 288 mL of B-52, containing all the essential B vitamins to relieve plant stress.

10.8 mL of Barricade is poured in next along with 360 mL of Scorpion Juice. These very effective Advanced Nutrients products are essential to fight and prevent fungal, bacterial, and viral as well as pest infestations. Barricade fortifies the walls of your cannabis cells, while Scorpion Juice imparts induced systemic resistance to my sinsemilla ladies, enabling their immune systems to counteract any invasions, whether by microorganisms or by bugs.

360 mL of Sensi Zym adds over eighty types of bioactive enzymes to the root systems of my plants. These help clean my grow medium of plant debris and aid in the absorption of viable nutrients by the root hairs.

21.6 grams of Piranha and Tarantula are added next during week 1 of vegetative growth, along with 86.4 mL of Voodoo Juice. The first two supply beneficial fungi and bacteria to the root zones of my ladies, which keep the harmful fungi and bacteria at bay. In addition, they help the roots grow to a larger size and aid in the absorption of nutrients by the plants.

The consistency of my watering solution goes from EC 1,14 or 800 ppm during week 1 gradually up to EC 1.85 or 1300 ppm during week 7 of vegetative growth. This reflects the growth of the plants and how they need more nourishment as they get bigger, much the same way that children need more food as they grow.

I used to move my hydroponic setup from under my grow light in order to accommodate the 15 pots for the intermediate stage, but it became too much hassle. So now I place a plywood board on top of my six large buckets and put the 15 smaller pots on top of that. In this way the younger plants are closer to the light source and still accessible for watering. I attach a pump to a short hose, dip one end into my pre-mix tank and put a watering nozzle on the other end. Presto, instant irrigation—I should say fertigation, implying not just water, but food as well.

posted by Wes @ 1:11 PM 0 comments links to this post

Friday, May 11, 2007


Curing in Candy Jars, Preventing Damping Off

While my sinsemilla buds and branches are drying, I am looking for large glass containers with lids to cure my medpot once the drying process is over. The humungous Connoisseur buds are much larger and they won’t fit into the curing containers I used for my last harvest.

I found the answer in of all places, our local candy shop. Squirrel wanted some candy, so she dragged me in there, but I’m very glad she did. The large display jars for the various sweets are just the right size for my colossal buds. I immediately offered cash to the store’s owner for 30 jars.

“I could sell them to you, but then what would I do with my candy,” was his answer. Instead, he gave me the phone number of his supplier, who happened to be at a nearby address. I phoned and rushed over. Presto, after a credit card transaction, I had my thirty “candy” jars ready for curing my pot.

While light is essential for growing plants, during drying and curing it helps the plant deteriorate and lose potency. I noticed that my prescription medications now come in dark green plastic containers for much the same reason.

I’ve built some shelves for my glass jars, but they won’t hold the 30 larger jars that I just bought, so it’s back to the drawing board. The shelves line one of the walls of the large, walk in closet where the drying is taking place in the dark.

I bought some wider shelves with enough space to fit the new jars and assembled the unit outside the closet so I wouldn’t interfere with the drying process. Since for curing cannabis it helps to have a sterile environment, I wiped the new shelves and the walls of the closet with Advanced Nutrients Wipe Out.

I also flushed my six bucket ebb and flow (flood and drain) hydroponic system again and again with fresh water, then I drained my reservoir completely and I wiped all my tanks and buckets and the walls of my grow room with Wipe Out.

It is time to wash my baked clay pebbles before planting the next batch of medicinal marijuana. Luckily, I use SensiZym. The over eighty live enzymes in this product enjoy munching on plant debris in my grow medium, converting them to absorbable nutrients for my plants.

But the pebbles still have to be washed and scrubbed thoroughly with warm water. Never use any chemical detergent to clean your grow medium, unless you want your next crop to taste like soap.

Harvest is also the time for planting new seeds, and I’ve done just that, in one inch rockwool cubes, under a plastic humidity cover in a tray under fluorescent grow tubes. I usually plant around 15 seeds, which with attrition and sex selection eventually whittle down to my six sinsemilla ladies.

At this point the rockwool cubes in the incubator are just soaked in distilled water, but as soon as the seeds germinate, they will be dipped into a half strength solution of my basic fert, Sensi Grow A & B, as well as B52 to help relieve stress.

Once the seeds germinate and the tiny seedlings grow roots, they one inch rockwool cube housing the seedling can be dipped into a solution of No Shock. Mix 10 mL (2 tsp) of No Shock into a Litre of water. Later, I place the one inch cube into a pre-dug hole in your grow medium very carefully, making sure that no delicate root filaments are damaged in the process.

I also pre-soak my rooting media with Jump Start, in order to stimulate root growth. I mix 1-2 mL per Litre of water. This can also be used as a foliar spray, before initial roots have developed. However, if you’re using it as a foliar spray, it should be mixed at a ratio of 30 mL per Litre.

If by any chance my seeds refuse to germinate in the rockwool cubes, I carefully dig them out and remove them with tweezers. My backup system is the tried and true wet paper towel method. You place the seeds in between two wet paper towels and put in a warm, dark place.

Stubborn seeds that have refused to germinate in rockwool most often than not will sprout tiny shoots in the wet paper towels. Of course, extra care should be taken in placing these tiny shoots back into the pre-drilled hole in the rockwool cubes for further incubation.

Never, under any circumstances, allow your tiny seedlings to dry out. On the other hand, don’t make them so wet that Damping Off will result. According to one of the foremost authorities on cannabis diseases, J. M. McPartland, most damping off is caused by a Pythium fungi, but Rhizoctonia, Botrytis, and Fusarium species could also be responsible.

Damping off kills seeds in soil or in any grow medium infected by the fungus. It also kills seedlings shortly after they emerge from the grow medium. The fungi usually attack seedling stems at the soil line. A brown, watery soft rot results, causing the plants to topple over.

Once my seedlings have four leaves in addition to the two cotyledon leaves, it will be time to transplant them into my grow medium, i.e. baked clay pebbles, under my 600W High Pressure Sodium lamp with a blue spectrum conversion bulb.

At that time my pre-mixed nutrient solution, featuring Sensi Grow A & B as my base nutrient, will be poured into my deep, 72 Liter reservoir, and the pumps will start to flood my buckets four times per 16-hour light period.

Barricade will be featured prominently in my nutrient solution, in order to allow its Potassium Silicate structure to strengthen the cell walls of my cannabis, enabling the plants to fight off and prevent many insect and pathogen attacks.

Also, every three weeks my seedlings will be sprayed with a mild solution of Scorpion Juice, which will impart an induced systemic resistance to many pests and pathogens.

posted by Wes @ 7:39 AM 0 comments links to this post

Saturday, May 05, 2007


Connoisseur Harvest--Resin-Coated Humungous Buds

I learn a great deal each time my six ladies approach maturity. Last week I flushed my six-bucket ebb and flow system with Final Phase, so this week I am irrigating my plants with pure water and examining my wonderfully enlarged buds to determine the best time for the harvest.

Harvesting your crop is the ultimate high for a truly dedicated grower. As you might recall, during week 3 of bloom I switched from my regular fert, Sensi Bloom A & B to the ultra special brand new super fert, Connoisseur A & B.

Soon after the switch, a miraculous growth spurt took place. Not only did the buds begin to swell, but the stems got fatter and the leaves looked like they were bursting with nutrients. The polyamino alcohols in Connoisseur, along with all the amino chelated ingredients in this premium product, caused the cell walls of my plants to become more elastic, and thus able to hold more carbohydrates.

With the increased carbo load (enhanced by the use of Carbo Load, an Advanced Nutrients Medical product) my buds had more nutrients to support their growth, so they grew and grew and couldn’t stop growing.

I still used Bud Blood, Big Bud, and Overdrive as indicated, during week 1 for the first bloom enhancer, weeks 2, 3, & 4 for the second, and weeks 5 & 6 for the third. The extra phosphorus and potassium contained in these products combined with the gourmet fine ingredients in Connoisseur and the sky became the limit!

Midstream during bloom, I used Sweet Leaf with its natural berry sugars to enhance the taste and smell of my harvest.

Not only did the size of my buds increase tremendously, but the bouquet, aroma, and (I must confess I clipped a sample) flavor were magnified, to the point that I had to introduce ozone generation in order to hide telltale odors from my nosy neighbors.

I’m growing Indica-Sativa hybrids, but this nutrient regimen is sure to work with just about any strain.

During the fourth week of flowering, my buds started to grow glandular trichomes on stalks, the tiny rods with knobs on the end of them best seen through a 30X magnifying glass.

Due to the Connoisseur, these trichomes became denser and denser through weeks 5, 6, & 7 of flowering, until now—we’re at the end of week 8—they are so densely packed that a very high potency is promised. (Judging from the sample smoke that floored me, I’d say that was a given.)

The tallest trichomes have clear, swollen, bulbous heads, which is the sign that the buds are ready for harvesting. Also, the flowers on the buds, called calyxes, have swollen, starting from the oldest at the base of my buds, all the way to the top, where the youngest flowers are. Swollen calyxes are also a sure sign that the harvest is at hand.

In all my years of growing medicinal marijuana, I have never seen calyxes as swollen as these. Prior to the wholesale swelling of the calyxes, the pistils at the base of the buds started to turn reddish brown, and by week 6 all the pistils have become that colour.

Now you must remember that these are unfertilized, female marijuana plants, but the calyxes are so swollen you’d swear they contained seeds.

Many growers say that you must harvest at night in order to give your plants that one last day of life-giving light, so I’m following their example.

I trimmed my plants of excess leaves the day before using sterilized scissors and gloves, so now I remove only the bud-filled flowering top of the plant as a unit. Did I mention that the proliferation of buds this time is astounding? I’ve never seen so many large-sized buds on each of my plants.

I manicure the buds on each plant very carefully, which means I cut the leaves encircling the buds, but not the ones covered with resin. It is better to do this while the plant is fresh in order to minimize trichome damage. Once the plant dries, it is harder to manicure.

Each flowering top is carefully hung upside down with wooden clothes pegs on a wire stretched at the top of a dark, large, walk-in closet for drying. A fan is put into the drying room to keep the air circulating and the temperature is kept around 70º F at no more than 50% humidity.

Judging from the size of my buds, this harvest will take more than five to ten days to dry, after which comes the curing, which I will discuss next week. Drying the flowering section of the cannabis plant as a unit takes a bit longer than if I had cut each floral cluster separately.

posted by Wes @ 7:30 AM 2 comments links to this post